The complex physical process of welding residual stress relieving bymeans of explosive technique is studied experimentally and numerically.The experiments are carried out in welded 16 MnR steel plates. In thenumerical simulations, the explicit dynamic finite element method isadopted. The results from experiments and computations are consistentwith each other. The mechanism of this technique is explained byconsidering the effect of stress wave reflection and superposition onthe redistribution of stresses in this process. Based on the abovestudies, some advises and parameters are provided to practicalapplications of this technique.